The subject matter described and/or illustrated herein relates generally to hermetically sealed containers, and more particularly, to pressure sensors for hermetically sealed containers.
A variety of containers are hermetically sealed. For example, containers may be hermetically sealed to secure against the entry of microorganisms and/or to protect the contents of the container. Food, chemicals, and pharmaceuticals are often packaged in hermitically sealed containers. Many devices such as electronics, semiconductors, thermostats, optical devices, and/or switches are also held within hermetically sealed containers. For example, some electromagnetic relays are contained within hermetically sealed containers.
The internal chamber of a hermetically sealed container may contain gas or may be evacuated such that the chamber contains a complete or partial vacuum. However, for at least some known hermetically sealed containers, a pressure or vacuum within the chamber is not determinable after the chamber has been hermetically sealed. Accordingly, a loss of pressure or vacuum within the chamber may not be detected, which may damage or inhibit operation of the contents of the chamber. For example, hermetically sealed relays typically have stationary and moving contacts, and an actuating mechanism supported within a hermetically sealed chamber. To suppress arching between the moving and stationary contacts, the hermetically sealed chamber may be filled with an inert and/or insulating gas or may be evacuated so that the contacts coact in a complete or partial vacuum. Once the chamber of at least some known relays has been hermetically sealed, the pressure or presence of a vacuum within the chamber is not determinable. Loss of gas pressure or vacuum within the hermetically sealed chamber of the relay may therefore not be detected. Operation of a relay after an undetected loss of gas pressure or vacuum may cause the relay to suffer from arching between the moving and stationary contacts, which may damage or inhibit operation of the relay.